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Lower
amines are gases while higher members are mostly liquids. Amines are
almost unpleasant, having fishy smell. In the pure state amines are
colourless, but in certain case they become coloured due to oxidation
and mixing of impurities.

2. Boiling point

In
amines, there are polar N-H bonds. Hence, in general they are polar.
More over, in amines, inter molecular hydrogen bonds are present,
leading to high boiling points in comparison to corresponding
hydrocarbons of the same molar mass.

All
the three classes of amines can form hydrogen bond with water. Hence
they are soluble in water. But higher amines are least soluble due to
the non-polar effect of big alkyl groups. Due to weaker hydrogen bonds
solubility of amines in water is less than that of alcohols.

Distinction between primary, secondary and tertiary amine Using Carbylamine Reaction

Primary amine (both aliphatic and aromatic) when warmed with chloroform and alcoholic KOH, gives isocyanides (carbylamines). This is called carbylamine reaction. Carbylamines has an offensive smell. This reaction is answered only by primary amine and hence to distinguish primary amine from other classes of amines.